An electrochemical capacitor including a chargeable and dischargeable electric storage element is widely used as a back-up power supply etc. In general, the electrochemical capacitor has a structure that an electric storage element and an electrolyte are enclosed in an insulating case. The insulating case has wirings that electrically connect the electric storage element enclosed to an outside of the case. The electrochemical capacitor requires that the wirings are protected from electrolytic corrosion accompanied by charge and discharge of the electric storage element.
For example, in an electrochemical capacitor described in Japanese Patent No. 4591931 (paragraph [0047], FIG. 1), a pair of electrodes (electric storage elements) and an electrolyte are housed in a concave shaped case, internal terminals are disposed within the concave shaped case, and a protective film having conductivity is formed between the electric storage elements and the internal terminals.
In a cell described in Japanese Patent No. 4817778 (paragraph [0041], FIG. 5), electric storage elements and an electrolyte are housed in a case, and a resin layer containing conductive particles is formed between the electric storage elements and a second metallization layer (a layer for conducing the electric storage elements and an outside of the case).
In any of the electrochemical devices described in Japanese Patent No. 4591931 and Japanese Patent No. 4817778, a layer (a film) for preventing a contact of the electrolyte and the wirings is disposed in order to prevent the electrolytic corrosion of the wirings by the electrolyte.